I think that was the intention. However from what Rob told me the driving conditions were near perfect, and both vehicles were using very little energy. They'd averaged 145 Wh/km even when driving at 110 km/h everywhere, so that 18 kWh wasn't used entirely.

It would be difficult to recharge the car to exactly the same point, because that point is somewhat fluid. If you recharge to 100% full you will use additional energy in cell balancing etc.

Maybe the next test is to effectively range-test the vehicle, with a generator nearby to provide the 5-hour full charge. Based on 266 ml/kWh that should require about 23 litres of diesel.

TBH non-eV people would see this as 0.4L/100km of convenience to fill up a diesel car wheneva and whereva with more range.
Really who could be bothered to save 55c/100km for all that electric car hassle?
Just looking at it from the other side of the coin.

I was thinking the same. Particularly if that's 18kwh into the Tesla battery. As it would have needed to produced more than 18kwh before charging losses. 4.4lt at $1.40lt for 18kwh = 34cent KWH less than grid power in SA